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Awhile back Aidan Baron (@Aidan_Baron) tweeted, "If you can't explain the pre-test probability, then you don't get to pick up the ultrasound.. no stats-no scan."
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This got me thinking about the way we approach testing in the pre-hospital setting. Are we performing EKG's, POC Labs, Ultrasound scans, and screens on patients just because we need to check off a box on our PCR, or do we truly believe the pre-test probably is high enough to justify the test? Does EMS have advanced enough illness scripts to even make that call?
My thought process had always been that this is a way of triaging your mental bandwidth, and that it was only applicable when seeing more than just one patient. A physician, PA, or NP could not physically perform every test on every person without complications and decreased attention to top tier priorities. In the back of a helicopter or ambulance, should we be over-testing?
In this podcast Chip Lange from TOTAL EM, and I discuss if pre-test probability and risk stratification is applicable to EMS.
References:
Fagan Nomogram http://www.pmean.com/definitions/fagan.htm
(Chip mentions this paper) Risk For Clinically Relevant Adverse Cardiac Events in Patients With Chest Pain
Illness Script Power-Point https://www.sgim.org/web-only/clinical-reasoning-exercises/illness-scripts-overview#